Agas is contained in a vertical piston-cylinder assembly. a vertical shaft whos cross-sectional area is 0.8 cm2 is attached to the top of the piston. determine the magnitude, f, of the force acting on the top of the piston, in n, required if the gas pressure is 3 bar. the masses of the piston and attached shaft are 24.5 kg and 0.5 kg, respectively. the piston diameter is 10 cm. the local atmospheric pressure is 1 bar. the piston moves smoothly in the cylinder and g = 9.81 m/s2 .